Canopy, filters & fan
Wiping the canopy and cleaning the extraction system are not the same thing, though they are easily confused. A gleaming canopy front is surface housekeeping; a full extraction clean addresses the plenum, ductwork and fan behind it and is verified by measurement. Only the second manages fire risk or satisfies an insurer.
The short answer
Wiping the canopy and cleaning the extraction system are not the same thing, though they are easily confused. A gleaming canopy front is surface housekeeping; a full extraction clean addresses the plenum, ductwork and fan behind it and is verified by measurement. Only the second manages fire risk or satisfies an insurer.
The detail
Canopy cleaning is what the kitchen does daily: the visible stainless of the hood is wiped down, the filters are washed, and the front of the system looks bright and hygienic. It is genuinely important for hygiene and appearance, and it keeps the entry point of the system in good order. But it addresses only the surfaces you can see and touch from the kitchen floor.
Full extraction cleaning follows the grease past that visible front. It cleans the plenum chamber directly behind the filters, the ductwork along its whole length, and the extract fan and discharge - the hidden parts where grease actually accumulates and where a fire would travel. This is the work TR19 Grease describes, and it needs access panels, specialist equipment and trained operatives, not a cloth.
The two are verified completely differently. Canopy cleaning is judged by eye - it looks clean. Full extraction cleaning is judged by measurement: deposits are tested with a Wet Film Thickness Test or Deposit Thickness Test at set points and must be brought below 50 microns, then recorded in a post-clean verification report with photographs. Appearance is not evidence; the measurement is.
This is why a clean canopy can sit in front of a dangerously greasy system. The parts that matter most for fire - the plenum, the duct, the fan - are exactly the parts a canopy wipe never touches. A kitchen can wipe its hood every day for years and still have a duct loaded well past the 200-micron mean limit, because the two activities address different halves of the system.
What it means for you
The practical danger is mistaking one for the other. A kitchen that wipes its canopy diligently can genuinely believe its extraction is cared for, while the ductwork and fan quietly load with grease. Understanding that canopy cleaning and system cleaning are separate jobs, on separate cycles, is what stops that false sense of safety.
It matters most when something goes wrong. TR19 Grease is recognised by insurers, and after a fire a claim can hinge on whether the system - not just the canopy - was cleaned and verified. A shelf of daily cleaning notes does not answer that question; a TR19 post-clean verification report of the full system does. The distinction is the difference between a covered loss and a contested one.
The right approach uses both, on their own rhythms. Daily canopy and filter cleaning by the kitchen keeps the front in order and slows the loading of the system; periodic full extraction cleaning by a qualified contractor addresses the hidden parts and produces the verification. One is housekeeping, the other is compliance, and a safe kitchen needs both rather than confusing the cheaper one for the whole.
The service behind the guide
Sibling guides
Why a canopy looks clean but isnt · Plenum cleaning above the filters · Pub kitchen extraction
Questions
Canopy cleaning is a daily wipe of the visible hood and filters. Full extraction cleaning addresses the plenum, ductwork and fan behind it and is verified by measurement. Only the second manages fire risk.
No. The canopy front can gleam while the plenum, duct and fan behind it are heavily greased. Those hidden parts are exactly what a canopy wipe never touches.
By measurement, not appearance. Deposits are tested with a Wet Film Thickness Test or Deposit Thickness Test and brought below 50 microns, then recorded in a post-clean verification report with photographs.
The full system clean. TR19 Grease is recognised by insurers, and after a fire a claim can hinge on whether the whole system was cleaned and verified - which daily canopy notes do not evidence.
Yes. Daily canopy and filter cleaning keeps the front in order and slows loading; periodic full extraction cleaning addresses the hidden parts and produces the verification. A safe kitchen needs both.
Phoenix Duct Clean · by the numbers
We clean the whole path - canopy, filters, plenum, ductwork and fan - and verify the result to TR19 Grease. Call or email for a clear quote and a certificate you can show your insurer.